richardsondx/expo-expert

Turn a prompt or a still image into a looping animated icon with real transparency — GPT Image / Nano Banana for the art, Seedance via OpenRouter for the motion, exact-unpremultiply matting for the alpha, animated WebP out. Use when asked to animate an app icon, make a 3D icon loop, produce a transparent animated asset, or add motion to flat icon art.

Build animations in React Native and Expo, making the decisions in the order that determines whether they feel right — should it animate, which thread it runs on, which properties, spring or timing, how the gesture hands off, how it degrades. Writes the implementation with Reanimated, Gesture Handler, Expo Router and expo-haptics. Use when animating anything in an Expo app, adding gestures, sheets, screen transitions, press feedback or haptics, or fixing motion that stutters on device. For web animation use animate.

Reverse-lookup glossary that turns a vague description of a web animation or motion effect into its exact term ("the bouncy thing when a popover opens" → Pop in; "the iOS rubber-band scroll" → Rubber-banding). Use when the user asks "what's it called when…", or describes a motion effect without knowing its name and wants the right word to prompt an AI or designer with. For naming an effect, not designing or building one.

Try to break a piece of UI by feeding it worst-case data — long names, unbreakable emails, one-letter names, missing fields, huge counts, zero items, long labels, non-Latin text, emoji, extreme numbers — then render it behind a "Demo data / Worst case" toggle and report everything that broke, with the fix for each. Use when the user asks to stress-test, break, or find edge cases in a component or screen, or to "try the worst case". For visual design critique use emil-design-eng; for motion use review-animations.

Use when writing, reviewing, or refactoring Expo / React Native apps for iOS, including state and Context data flow, component composition, resizable layouts, safe areas, performance, FlatList, Expo Router navigation, sheets, animation, accessibility, charts, Liquid Glass, SDK version checks, profiling, and animated 3D icons. Also use for large-display, tablet, and foldable layouts (useWindowDimensions, two-column reflow), Dynamic Type, and reduced-motion handling.

Search a codebase or UI for places that don't animate but should, and reject everything that shouldn't. Read-only; it proposes motion with exact values, it does not implement it. Use when the user asks "what could be animated here?" or wants to "make this feel more alive". For fixing existing animations, use improve-animations or review-animations instead.

Survey a codebase's animation and motion code as a senior motion advisor, then produce a prioritized audit and self-contained implementation plans for other agents (or cheaper models) to execute. Read-only on source code — it plans improvements, it does not apply them. Use when the user asks to "improve the animations", "audit the motion", "make this app feel better", or wants a roadmap of animation fixes rather than a review of a single diff.

Build multiple genuinely different versions of a UI piece you describe, rendered behind a visual picker so you can flip through them live and promote the one that feels right. Only runs when explicitly invoked; it does not trigger on its own.

Find the animations an interface doesn't need and remove them — motion on keyboard actions, high-frequency surfaces, functional data, and decoration with no purpose — then clean up what they leave behind. Edits code, but only to subtract; it never adds or retunes motion. Use when the user says the app "feels slow", "has too much animation", "feels over-animated", wants to "tone down the motion", or asks what animations to remove. For finding places that should animate, use find-animation-opportunities; for fixing animations that should stay, use improve-animations or review-animations.

Reviews animation and motion code against a high craft bar derived from Emil Kowalski's design engineering philosophy. Default to flagging; approval is earned.